1. Field of the Invention
The present invention relates to a water purifier to filter and purify tap water, and especially relates to a water purifier for use in a typical home.
The present application is based on Japanese Patent Application No. 2000-95914, the contents of which are incorporated by reference.
2. Description of Related Art
Water purifiers to purify tap water have been used, because of contamination of water resources and demands for obtaining water with a pleasant taste. Water purifiers which have the functions of removing chlorine odor, mold odors and trihalomethanes from tap water by using an absorbent such as activated carbon, and of removing bacteria or impurities by using porous hollow fiber membranes are known.
As one type of water purifier 10, a water purifier mounted a faucet directly as shown in FIG. 11 is on the market and is used in general households. In this water purifier 10, the main housing 1 is attached to the faucet 2 with the adapter 3 and the fixed ring 4. By operating the switching lever 5, it is possible to switch between tap water and purified water by the switching mechanism built into the main housing 1. Water purification cartridge 17 is mounted on the main housing 1, and a flow meter 20 is also provided. In this water purifier 10, when the switching lever 5 is set to the purified water position and tap water flows from the faucet 2, it is led to the water purification cartridge 17 by the switching mechanism. And after passing through the filtering medium and being purified, it passes through the water flow meter 20 and flows out downwards from the purified water outlet 9.
The main housing 1 is provided with a gear reduction type flow meter 20 which measures the integrated outflow of purified water as means of knowing the replacement life of the water purification cartridge 17. Thus, there is a mechanism for periodically replacing the water purification cartridge 17 according to the display of the flow meter 20. As the display, the indicator portion 21 gradually appears downwards as the outflow increases and it is possible to recognize the outflow in combination with it and the graduations and letters of the graduated portion 22.
Further, a flow meter is disclosed in Japanese Unexamined Patent Application, First Publication No. Hei 8-285642, and Japanese Unexamined Patent Application, First Publication No. Hei 8-318113 discloses a filter cartridge for a water purifier which uses this flow meter. In this flow meter, an index Indicator portion) provided on the final gear rotates with an increase of flow, and the graduations (graduated portion) indicate the amount of rotation, so that the amount of flow can be recognized. Because this constitution makes use of planetary gears having the same center axle, it can be relatively compact and inexpensive.
[1](i) Incidentally, for a water purifier to replace water purification cartridges, even if a flow meter is provided, if the flow meter cannot be reset (returned it to its original setting) when the water purification cartridge is replaced, it is difficult to know when to replace the new purification cartridge practically.
However, in the flow meter disclosed in the above-indicated Japanese Unexamined Patent Application, First Publication No. Hei 8-285642 and Japanese Unexamined Patent Application, First Publication No. Hei 8-318113, there is no provision of a mechanism which makes it possible to reset (return to the original setting) the indicator portion for the graduated portion. As a result, to recognize the amount of movement of the indicator portion, it is necessary to remember or record the original position of the indicator portion, when the water purification cartridge is started to use, and to ascertain the position of the end point for that original position, so the way of use is very troublesome and inconvenient. This problem is especially notable in homes where the water purification cartridge is frequently replaced.
The water purifier shown in the above-indicated FIG. 11 is provided with a mechanism that automatically resets the indicator portion 21 for the fixed graduated portion 22 by using the fit with the external shape of the water purification cartridge 17 when the water purification cartridge 17 is mounted on the main housing 1 at the time of replacing the water purification cartridge 17.
However, the mechanism to perform the automatic resetting is complex, and it is combined and built into the interior of the flow meter 20. Therefore, the size of the main housing 1 is increased to the volume of the mechanism, and which is not preferable, especially such a water purifier mounted a faucet directly which is required to be compact. Further, since this increases the amount of material and the number of parts, the assembly cost also increases, which leads to an increase of the product cost.
(ii) Further, in the water purifier 10 shown in FIG. 11 and Japanese Unexamined Patent Application, First Publication No. Hei 8-285642, it is inconvenient to clean. Because the graduated portion 22 cannot be detached from the flow meter 20 and even if the front or rear of the graduated portion 22 becomes contaminated with bacteria or mold, it cannot be soaked with detergent and washed or its rear portion cannot be scrubbed. And further, if it becomes heavily soiled, it cannot be replaced, even if it is desired to do so.
(iii) Furthermore, the water purifiers provided with the flow meters disclosed in Japanese Unexamined Patent Application, First Publication No. Hei 8-285642 and Japanese Unexamined Patent Application, First Publication No. Hei 8-318113, and the water purifier 10 shown in FIG. 11 can serve as a guides for the replacement time only for a predetermined type of purification cartridge, but if a water purification cartridge with a different lifetime is mounted on the water purifier, it is not possible to know the replacement time for it. As a result, the users cannot use a water purification cartridge with a longer lifetime against their will On the other hand, the makers must produce other water purifier products, which is illogical.
[2](iv) Furthermore, in the water purifier of Japanese Unexamined Patent Application, First Publication No. Hei 8-318113, because the flow meter is built into the water purification cartridge, the cost of the flow meter is added to the cost of the water purification cartridge, which increases the product cost of the water purification cartridge. In this case, the frequency of replacing the water purification cartridge is high, so the users must bear a considerable economic burden, which is not preferable from the economical point of view.
Further, because the flow meter like the water purification cartridge becomes disposable, it is also discarded as waste whenever the water purification cartridge is replaced. Particularly in the water purifier mounted to a faucet directly which have a short lifetime of water purification cartridge, because the frequency of replacement is high and the amount of flow meters discarded as waste will be large, which was a problem since it is environmentally unfavorable.
(v) Further, in the water purifier 10 of the prior art or the water purifier provided with a flow meter disclosed in Japanese Unexamined Patent Application, First Publication No. Hei 8-318113, when the flow meter itself becomes dirty, the flow meter cannot be detached and soaked with detergent and washed, and cannot be scrubbed, so it is inconvenient to clean it. And when it becomes very dirty, it cannot be replaced even if it is desired to do so. What is more, in case the flow meter breaks down, it cannot be detached and repaired, and so it cannot be replaced, which is the problem that maintenance is inconvenient in that point.
(vi) In the material of the rotating members used as components of the flow meter, polyacetal resin is generally favored, because of its excellent abrasion resistance and the like. However, in recent years the flow meter is especially requested to be more compact and improve durability, and the abrasion resistance and strength of polyacetal resin are insufficient.
(vii) Further, if the rotating members of the flow meter become abraded or rupture due to an increase of water flow over a long time, or if foreign matter flows into the flow meter at the time of replacing the water purification cartridge, and becomes temporarily stuck, even though the water flow increases, the rotating portion will not move, and there is a fear that the indicator portion 21 will break down and stop. Although the speed of the indicator portion 21 after the final speed reduction is generally very slow, and the only way to ascertain whether it has malfunctioned and stopped is to observe the indicator portion 21, which is visible, over a long time, and it should cost a lot of work and time to do that. If users should neglected the observation, they would continue to use the water purifier without noticing that it has broken, and they would be liable to continue to use the water purification cartridge whose lifetime has expired.
(viii) Further, in the water purifier 10 of prior art and the water purifier provided with the flow meter of Japanese Unexamined Patent Application, First Publication No. Hei 8-318113, if they are used over a long time, the instantaneous flow of purified water decrease due to clogging to the filtration material in the water purification cartridge, and so the time required to draw water becomes longer, which loses the convenience of use. To solve that problem, it is desired to provide an indicator which has functions of showing the state of the instantaneous flow and of promoting replacement of the new water purification cartridge. For example, Japanese Unexamined Patent Application, First Publication No. Hei 5-7867 and Japanese Unexamined Patent Application, First Publication No. Hei 9-229731 disclose such indicators.
However, in these indicators of prior art, it is basically necessary for them to be provided with a spring and a resistive body on the water flow passage of the inside the water purifier and a transparent housing to build into them and a window and graduations on the main housing of the water purifier. So the size and cost of the water purifier will inevitably increase. But the water purifier mounted a faucet directly is especially requested to be compact and cheep, so it is practically difficult to build them in combination with a flow meter.
The present invention was made in order to solve the above problems, and therefore aims to provide an excellent water purifier which is compact and low cost constitution and has the flow meter which can be easily and accurately be reset and be easily kept clean and work for several types of water purification cartridges.
Further, another goal is to provide an excellent water purifier, which is compact and low cost, with a built-in flow meter of excellent durability and compact size, which can further be to used efficiently from the environmental and economical points of view, which makes allowance easily and accurately to notice of malfunctions of the flow meter, and which is also provided with an indicator function which can recognize the time to replace the water purification cartridge, when the instantaneous flow of purified water decreases.
The water purifier according to a first embodiment of the invention is provided with a flow meter which measures the integrated flow of purified water which has passed through the water purification cartridge, wherein the flow display of the said flow meter is characterized by comprising an indicator portion which rotates with an increase of the flow, and a graduated portion which can rotate around an axis which is the same as that of said indicator portion.
In this water purifier, to reset of the flow meter can be carried out accurately and easily without building into the main body an internal flow meter with a complex mechanism for resetting the flow meter display automatically. Consequently it is possible that the main body becomes small, the amount of material and the number of parts decrease, and the cost is reduced. And a compact and low cost product can be achieved.
It is desirable to form an insertion groove at said graduated portion so that the rotation operation of the graduated portion can be carried out by a coin or the like.
In this way, the resetting operation can simply and easily be carried out by ordinary demanders.
Further, it is desirable that the graduated portion have a curvature so that it can project outwards, with an insertion slot formed near the center thereof since this formation makes the graduated portion possible to increase the strength.
Further, it is preferable that the graduated portion can be detachable from the flow meter.
In this way, the graduated portion can be easily cleaned or replaced, so it keeps clean.
Further, it is desirable to provide markings on the graduated portion which serve as guides for the replacement time for several types of water purification cartridge having different lifetimes
As a result, it is possible to use several types of water purification cartridges, which can provide a great deal of convenience and economy for the users.
The water purifier according to claim 6 is characterized by being provided with a main housing and a water purification cartridge mounted on the main housing, the flow meter which measures the integrated flow of purified water passing through the water purification cartridge is detachably built into the main housing.
In this way, the flow meter of excellent durability and compact size is built to being used efficiently from economical and environmental points of view. Moreover, it is possible to clean or replace the flow meter.
It is desirable for the flow meter to comprise an impeller which is rotated by the water flow, a plurality of planetary gears which sequentially transmit the rotation by planetary motion and reduce the speed of rotation, and an indicator portion which interlocks the final rotating gear, and a housing which contains these members.
This is why the water purifier may be small and low cost.
The water purifier according to claim 8 is characterized by being provided with a flow meter which measures the integrated flow of purified water based on the rotation of an impeller which rotates with the flow of purified water through the water purification cartridge, wherein the impeller of the flow meter is visible from the outside.
As a result, malfunctions of the flow meter can be easily and accurately ascertained.
It is desirable for the impeller to be set to start rotating at or above a prescribed value of the water flow.
As a result, an indicator function is provided which recognizes the time to replace the water purification cartridge, when the instantaneous flow of purified water is reduced. Furthermore, the water purifier can be constituted in a compact manner and at low cost, so it provides a great deal of convenience and economy for the users.
Further, it is desirable for the rotating members used in the flow meter to be made of a polyacetal resin which contains carbon.
It is possible for the flow meter to be more compact and to have a longer lifetime, because the rotating members have extremely high abrasion resistance and durability.
It is desirable to use a porous hollow fiber membrane as the filtration material of the water purification cartridge.
This is because it has such an excellent filtration performance as to remove bacteria, and it has excellent performance in removing impurities.
It is desirable to provide the flow meter after the final stage of the water purification cartridge.
As a result, since impurities have been removed by porous hollow fiber membrane in the water purification cartridge and the flow meter measures the flow of purified water, so that breaking down of the flow meter can be prevented due to clogging to the rotating members by impurities and the like
The present invention takes the above notable effects, especially on water purifier mounted a faucet directly, that is, on water purifier where frequency of replacing the water purification cartridge is expected to be high comparatively.